fix: use SYSCONFDIR in error message

[i3/i3status] / src / print_ip_addr.c

diff --git a/src/print_ip_addr.c b/src/print_ip_addr.c
index 6ddd35a125ef6c6d50e9ea522f1eff29bfa10b4e..463412f57be2673f8a8fbb0ba65d20a9658752dc 100644 (file)
--- a/src/print_ip_addr.c
+++ b/src/print_ip_addr.c
@@ -1,7 +1,9 @@
-// vim:ts=8:expandtab
-#include <netinet/in.h>
-#include <sys/socket.h>
+// vim:ts=4:sw=4:expandtab
+#include <config.h>
 #include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -11,57 +13,93 @@
 
 #include "i3status.h"
 
+/*
+ * Return a copy of the .ifa_name field passed as argument where the optional
+ * IP label, if present, is removed.
+ *
+ * example:
+ * - strip_optional_label("eth0") => "eth0"
+ * - strip_optional_label("eth0:label") => "eth0"
+ *
+ * The memory for the returned string is obtained with malloc(3), and can be
+ * freed with free(3).
+ *
+ *
+ */
+static char *strip_optional_label(const char *ifa_name) {
+    char *copy = sstrdup(ifa_name);
+
+    char *ptr = strchr(copy, ':');
+
+    if (ptr) {
+        *ptr = '\0';
+    }
+
+    return copy;
+}
+
 /*
  * Return the IP address for the given interface or "no IP" if the
  * interface is up and running but hasn't got an IP address yet
  *
  */
-const char *get_ip_addr(const char *interface) {
-        static char part[512];
-        socklen_t len = sizeof(struct sockaddr_in);
-        memset(part, 0, sizeof(part));
-
-        struct ifaddrs *ifaddr, *addrp;
+const char *get_ip_addr(const char *interface, int family) {
+    static char part[512];
+    socklen_t len = 0;
+    if (family == AF_INET)
+        len = sizeof(struct sockaddr_in);
+    else if (family == AF_INET6)
+        len = sizeof(struct sockaddr_in6);
 
-        getifaddrs(&ifaddr);
+    memset(part, 0, sizeof(part));
 
-        if (ifaddr == NULL) {
-                (void)snprintf(part, sizeof(part), "E: down");
-                return part;
-        }
+    struct ifaddrs *ifaddr, *addrp;
+    bool found = false;
 
-        addrp = ifaddr;
+    getifaddrs(&ifaddr);
 
-        /* Skip until we are at the AF_INET address of interface */
-        for (addrp = ifaddr;
+    if (ifaddr == NULL)
+        return NULL;
 
-             (addrp != NULL &&
-              (strcmp(addrp->ifa_name, interface) != 0 ||
-               addrp->ifa_addr == NULL ||
-               addrp->ifa_addr->sa_family != AF_INET));
+    /* Skip until we are at the input family address of interface */
+    for (addrp = ifaddr; addrp != NULL; addrp = addrp->ifa_next) {
+        /* Strip the label if present in the .ifa_name field. */
+        char *stripped_ifa_name = strip_optional_label(addrp->ifa_name);
 
-             addrp = addrp->ifa_next) {
-                /* Check if the interface is down */
-                if (strcmp(addrp->ifa_name, interface) == 0 &&
-                    (addrp->ifa_flags & IFF_RUNNING) == 0) {
-                        freeifaddrs(ifaddr);
-                        return NULL;
-                }
+        bool name_matches = strcmp(stripped_ifa_name, interface) != 0;
+        free(stripped_ifa_name);
+        if (name_matches) {
+            /* The interface does not have the right name, skip it. */
+            continue;
         }
 
-        if (addrp == NULL) {
-                freeifaddrs(ifaddr);
-                return "no IP";
+        if (addrp->ifa_addr != NULL && addrp->ifa_addr->sa_family == family) {
+            /* We found the right interface with the right address. */
+            break;
         }
 
-        int ret;
-        if ((ret = getnameinfo(addrp->ifa_addr, len, part, sizeof(part), NULL, 0, NI_NUMERICHOST)) != 0) {
-                fprintf(stderr, "getnameinfo(): %s\n", gai_strerror(ret));
-                freeifaddrs(ifaddr);
-                return "no IP";
+        /* Check if the interface is down. If it is, no need to look any
+         * further. */
+        if ((addrp->ifa_flags & IFF_RUNNING) == 0) {
+            freeifaddrs(ifaddr);
+            return NULL;
         }
 
+        found = true;
+    }
+
+    if (addrp == NULL) {
         freeifaddrs(ifaddr);
-        return part;
-}
+        return (found ? "no IP" : NULL);
+    }
 
+    int ret;
+    if ((ret = getnameinfo(addrp->ifa_addr, len, part, sizeof(part), NULL, 0, NI_NUMERICHOST)) != 0) {
+        fprintf(stderr, "i3status: getnameinfo(): %s\n", gai_strerror(ret));
+        freeifaddrs(ifaddr);
+        return "no IP";
+    }
+
+    freeifaddrs(ifaddr);
+    return part;
+}